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Finding the Fourth Proportional to 642.75, 964.13 and 300.75

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Solution

The fourth proportional to 642.75, 964.13 and 300.75 is: 451.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.75 : 964.13 = 300.75 : x
  2. Step 2: Convert to fraction form
    642.75/964.13 = 300.75/x
  3. Step 3: Cross multiply
    642.75x = 964.13 × 300.75
  4. Step 4: Simplify right side
    642.75x = 289,960.59
  5. Step 5: Solve for x
    x = 289,960.59/642.75
  6. Step 6: Final answer
    x = 451.13

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.